• 제목/요약/키워드: methanol activation

검색결과 227건 처리시간 0.028초

Characterization of a Novel Alkaline Family VIII Esterase with S-Enantiomer Preference from a Compost Metagenomic Library

  • Lee, Hyun Woo;Jung, Won Kyeong;Kim, Yong Ho;Ryu, Bum Han;Kim, T. Doohun;Kim, Jungho;Kim, Hoon
    • Journal of Microbiology and Biotechnology
    • /
    • 제26권2호
    • /
    • pp.315-325
    • /
    • 2016
  • A novel esterase gene, est7K, was isolated from a compost metagenomic library. The gene encoded a protein of 411 amino acids and the molecular mass of the Est7K was estimated to be 44,969 Da with no signal peptide. Est7K showed the highest identity of 57% to EstA3, which is an esterase from a drinking water metagenome, when compared with the enzymes with reported properties. Est7K had three motifs, SMTK, YSV, and WGG, which correspond to the typical motifs of family VIII esterases, SxxK, Yxx, and WGG, respectively. Est7K did not have the GxSxG motif in most lipolytic enzymes. Three additional motifs, LxxxPGxxW, PLGMxDTxF, and GGxG, were found to be conserved in family VIII enzymes. The results of the phylogenetic analysis and the alignment study suggest that family VIII enzymes could be classified into two subfamilies, VIII.1 and VIII.2. The purified Est7K was optimally active at 40ºC and pH 10.0. It was activated to exhibit a 2.1-fold higher activity by the presence of 30% methanol. It preferred short-length p-nitrophenyl esters, particularly p-nitrophenyl butyrate, and efficiently hydrolyzed glyceryl tributyrate. It did not hydrolyze β-lactamase substrates, tertiary alcohol esters, glyceryl trioleate, fish oil, and olive oil. Est7K preferred an S-enantiomer, such as (S)-methyl-3-hydroxy-2-methylpropionate, as the substrate. The tolerance to methanol and the substrate specificity may provide potential advantage in the use of the enzyme in pharmaceutical and other biotechnological processes.

Methanol Extract of Goat's-beard (Aruncus dioicus) Reduces Renal Injury by Inhibiting Apoptosis in a Rat Model of Ischemia-Reperfusion

  • Baek, Hae-Sook;Lim, Sun-Ha;Ahn, Ki-Sung;Lee, Jong-Won
    • Preventive Nutrition and Food Science
    • /
    • 제17권2호
    • /
    • pp.101-108
    • /
    • 2012
  • Interruption or prolonged reduction and subsequent restoration of blood flow into the kidney triggers the generation of a burst of reactive oxygen species (ROS), leading to injury in the tubular epithelial cells. In this study, we determined whether methanol extract of goat's-beard (Aruncus dioicus) (extract) could prevent this ischemia/reperfusion injury. When in vitro radical scavenging activity of the extract was measured using a DPPH radical quenching assay, the extract displayed slightly lower activity than ascorbic acid. One hour after administration of the extract (400 mg/kg) by intraperitoneal injection in rats, renal ischemia/reperfusion injury was generated by clamping the left renal artery for forty minutes, followed by 24 hr restoration of blood circulation. Prior to clamping the left renal artery, the right renal artery was removed. Compared with the vehicle-treated group, pretreatment with the extract significantly reduced the tubular epithelial cell injury by 37% in the outer medulla region, and consequently reduced serum creatinine concentration by 39%. Reduction in the cell injury was mediated by attenuation of Bax/Bcl-2 ratio, inhibition of caspase-3 activation from procaspase-3, and subsequent reduction in the number of apoptotic cells. Thus, goat's-beard (Aruncus dioicus) might be developed as a prophylactic agent to prevent acute kidney injury.

Effect of Methanol Extract from Cassia mimosoides var. nomame on Ischemia/Reperfusion-induced Renal Injury in Rats

  • Baek, Hae Sook;Lim, Sun Ha;Ahn, Ki Sung;Lee, Jong Won
    • 대한본초학회지
    • /
    • 제28권6호
    • /
    • pp.135-143
    • /
    • 2013
  • Objectives : The purpose of this study was to determine whether the methanol extract of Cassia mimosoides var. nomame Makino, a naturally growing plant in Korea, could prevent the renal-ischemia/reperfusion injury in a rat model or not. Methods : The radical scavenging activities of the extracts, and ascorbic acid as a positive control, were measured in vitro. At one hour after an intraperitoneal injection of the extract (400 mg/kg), renal ischemia/reperfusion injury was generated by 40 min clamping of the left renal artery in rats. After renal ischemia/reperfusion and 24 hr restoration of blood circulation, the serum creatinine concentration was measured. And the extent of epithelial cell injury and apoptosis was assessed by various staining technologies. The Bax/Bcl-2 ratio and activated caspase-3 were assessed by immunohistochemistry. Results : The extract showed a slightly lower level of radical scavenging activity than that of ascorbic acid. Compared to those of the vehicle-treated group, the extract-treated group displayed a significantly smaller tubular epithelial cell injury of 54% reduction in the outer medulla region and a lower serum creatinine concentration of 50% reduction. It seems that the reduction in cellular injury is due to the attenuation of the Bax/Bcl-2 ratio, and the inhibition of caspase-3 activation by the extract of Cassia mimosoides. Conclusions : Cassia mimosoides var. nomame Makino could be a good candidate for a prophylactic agent against the ischemia/reperfusion/induced kidney injury.

Inhibitory Effects of Saururus Chinensis Extracts on Osteoclast Differentiation

  • Shim, Ki-Shuk;Kim, Soon-Nam;Kim, Myung-Hee;Kim, Young-Sup;Ryu, Shi-Yong;Min, Yong-Ki;Kim, Seong-Hwan
    • Natural Product Sciences
    • /
    • 제14권2호
    • /
    • pp.113-117
    • /
    • 2008
  • Saururus chinensis is a commonly used folk herb for the treatment of edema and liver diseases in Korea. To study the biological activity of Saururus chinensis in bone metabolism, we evaluated the effect of its extracts on osteoclast differentiation in vitro using primary mouse bone marrow-derived macrophages. Methanol extract (ME) from dried roots of Saururus chinensis was partitioned into methylene chloride (MF), ethyl acetate (EF), n-butanol (BF) and water fractions (WF). Tartrate-resistance acid phosphatase (TRAP) activity assay and western blot analysis were performed to determine the effect on osteoclast differentiation and mitogen-activated protein (MAP) kinases activation. ME, MF and EF dramatically inhibited receptor activator of ${NF-kB}$ ligand (RANKL)-induced formation of multinucleated osteoclasts and activation of MAP kinases. This study firstly demonstrated that ME, MF and EF of Saururus chinensis have the potential to inhibit the osteoclast differentiation, which results from the inhibition of MAP kinases activations in part.

황련 추출물의 분획화 및 BV2 microglial cells에서 LPS에 의해 유도되는 nitric oxide 생성억제효과 검정 (Effects of subfractions of Coptidis Rhizoma extract on the nitric oxide production in LPS-stimulated BV2 microglial cells)

  • 정효원;박용기
    • 대한본초학회지
    • /
    • 제22권2호
    • /
    • pp.73-78
    • /
    • 2007
  • Objectives : Uncontrolled activation of microglia may directly toxic to neurons by releasing various substances such as inflammatory cytokines, nitric oxide(NO), prostaglandin E2 and superoxide. In this study, the effects of the several subfractions isolated from Coptidis Rhizoma extract were investigated on NO production in LPS-stimulated BV2 microglial cells, Methods : Coptidis Rhizoma extract prepared with 80% methanol, and then fractionated with ethylacetate, chloroform, n-butanol and water. BV2 cells were pretreated four subfractions of Coptidis Rhizoma with various concentrations, and then stimulated with LPS. Cytotoxicity of each fraction was measured by MTT assay. NO production was determined in culture surpernatants by Griess reagent. Results : Ethylacetate, chloroform and butanol fractions of Coptidis Rhizoma extract significantly decreased LPS-induced NO production in BV2 cells as a dose-dependent manner without cytotoxicity. Ethylacetate fraction of Coptidis Rhizoma extract was most effective on inhibition of NO production in LPS-stimulated BV2 cells compared with other fractions. Conclusion : This data indicates that Ethylacetate fraction of Coptidis Rhizoma extract shows strong antiinflammatory effects through inhibition of LPS-induced microglial activation.

  • PDF

속수자가 HT-29 대장암세포의 활성 및 세포사멸에 미치는 영향 (Effects of Euphorbiae lathyridis Semen on cell apoptosis in HT-29 human colon cancer cells)

  • 이제현;정선주;박용기
    • 대한본초학회지
    • /
    • 제22권2호
    • /
    • pp.65-72
    • /
    • 2007
  • Objectives : In this study, we investigate that Euphorbiae lathyridis Semen extract contributes to growth inhibitory effect and anti-cancer activity on the HT-29 human colon cancer cells. Methods : Euphorbiae lathyridis Semen was extracted from the Semen of the plant using 80% Methanol. The Euphorbiae lathyridis Semen extract was treated to different concentrations for 24 hr, 4Shr or 72hr. Growth inhibitory effect was analyzed by measuring FACS study and MTT assay. Cell apoptosis was confirmed by surveying caspases cascades activation using Westem blot. Results : Exposure to Euphorbiae lathyridis Semen extract (0.4mg/ml) results in an inhibitory effect on cell growth in HT-29 cells. Growth inhibition by Euphorbiae lathyridis Semen extract in HT-29 cells was related with the inhibition of proliferation and induction of apoptosis. The Euphorbiae lathyridis Semen extract induces DNA fragmentation in HT-29 cells. Furthermore, Euphorbiae lathyridis Semen extract induces cell apoptosis through the activation of caspases-3, caspase-9 and PARP cleavage. Conclusion : Euphorbiae lathyridis Semen extract induces apoptosis in human colon cancer cells, therefore, we suggest that Euphorbiae lathyridis Semen extract can be used as a novel class of anti-cancer drugs.

  • PDF

Metoclopramide-Polyvinylpyrrolidone 공침물(共沈物)에 관(關)한 생물약제학적(生物藥劑學的) 연구(硏究) (Biopharmaceutical Studies on the Coprecipitate of Metoclopramide-Polyvinylpyrrolidone)

  • 용재익;유봉신
    • Journal of Pharmaceutical Investigation
    • /
    • 제10권3호
    • /
    • pp.33-45
    • /
    • 1980
  • In order to increase the solubility of metoclopramide, various ratio coprecipitates with polyvinylpyrrolidone (M.W. 40,000) were prepared. The experiments of the solubility, physicochemical characteristics were quantitatively developed. The solubility increased as the ratio of rnetoclopramide to polyvinylpyrrolidone in metoclopramide-polyvinylpyrrolindone coprecipitate increased. In powder state, the dissolution rate of metoclopramide-polyvinylpyrrolidone coprecipitate was greater than that of metoclopramide and metoclopramide-polyvinylpyrrolidone physical mixture. Dissolution characteristics of non-disintegrating disk with constant surfacearea was in accord with Noyes-Nernst equation. The intrinsic dissolution rate, G, at $37^{\circ}C$ was $3.98{\times}10^{-7}M/cm^2{\cdot}min$ for metoclopramide, $2.26{\times}10^{-6}\;M/cm^2{\cdot}min$ for 1 : 5 metoclopramide-polyvinylpyrrolidone coprecipitate, respectively. Accordingly, activation energy of metoclopramide was 15,061cal/M, 9,178cal/M for 1 : 5 metoclopramide-polyvinylpyrrolidone coprecipitate and the activation energy decreased as the coprecipitate was formed. X-ray diffraction study revealed the fact that metoclopramide was crystalline, in contrast, there was no crystallinity evident in the 1 : 5 metoclopramide-polyvinylpyrrolidone coprecipitate. There was no difference between physical mixture and coprecipitate in TLC, UV and NMR studies. From the comparision between physical mixture and coprecipitate in IR spectrum, the interaction such as association between metoclopramide and polyvinylpyrrolidone was considered. But the association was easily dissociated in methanol solution.

  • PDF

Cyclitol 유도체합성을 위한 Furfural 유도체의 반응에 관한 연구. Furfural, 5-Bromo-및 5-Methylfurfural의 Cannizzaro 반응 (Reaction of Furfural Derivatives. Cannizzaro reaction of Furfural, 5-Bromo-and 5-Methylfurfural)

  • 손주환;김용인;남기대
    • 대한화학회지
    • /
    • 제16권5호
    • /
    • pp.290-297
    • /
    • 1972
  • 메탄올(95%) 용매내 $0{\sim}40^{\circ}C$에서 푸르푸랄, 5-메틸 및 5-브로모푸르푸랄의 알코올성 수산화칼륨에 의한 Cannizzaro 반응은 4차반응이며 푸르푸랄은 5-메틸푸르푸랄보다 3배, 5-브로모푸르푸랄은 푸르푸랄보다 10배 빠르게 진행된다. 그리고 이 반응에서 푸르푸랄, 5-메틸푸르푸랄, 5-브로모푸르푸랄의 활성화에너지는 각각 10.46 Kcal/mole, 16.27 Kcal/mole, 9.62 Kcal/mole이며 ${\Delta}H^{\neq}$${\Delta}S^{\neq}$를 계산한 바 5-브로모푸르푸랄, 푸르푸랄, 5-메틸푸르푸랄의 순으로 증가 되었다.

  • PDF

Effect of Glycyrrhizae Radix on the Expression of UDP-Glucuronosyltransferase-1A1 (UGT1A1) in Rat Liver

  • Moon, A-Ree;Lee, Song-Deuk
    • Biomolecules & Therapeutics
    • /
    • 제4권3호
    • /
    • pp.280-284
    • /
    • 1996
  • Licorice has been widely used in combination with other herbs or synthetic drugs for various disorders. In an effort to study the effect of licorice roots (Glycyrrhizae Radix, GR) and glycyrrhizin on the hepatic glucuronidation, we have previously found that the pretreatment of GR or glycyrrhizin for 6 days resulted in a marked increase in the enzymatic activity of 3-methylcholanthrene (3-MC)-inducible hepatic UDP-glucuronosyltransferase (UGT) isozyme that has high affinity toward phenolic substrates (p-nitrophenol form, UGTIA) in Sprague-Dawley rats. As an approach to elucidate the mechanism for the enzyme activation by licorice in rat liver, we examined the levels of hepatocellular mRNAs for UGTIA upon the treatment of GR or glycyrrhizin. The hepatic mRNAs were extracted from Sprague-Dawley rats and Wistar rats after the treatment of the methanol extract of GR (1 g/kg, p.o.), glycyrrhizin (23 mg/kg, p.o.) for 6 days, or 3-MC (40 mg/kg, i.p.) for 3 days. Using the UGT1A1 CDNA as a probe, we found that the mRNAs for the enzyme were induced by 3-MC treatment while those were influenced neither by GR nor by glycyrrhizin in both strains of rats. These results indicate that the activation of rat liver UGTI A by licorice and glycyrrhizin was not due to the induction of mRNAs for the enzyme.

  • PDF

Photoionization of N,N,N',N'-Tetramethyl-p-phenylenediamine in Polar Solvents

  • Min Yeong Lee;Du Jeon Jang;Minyung Lee;Du-Jeon Jang;Dongho Kim;Sun Sook Lee;Bong Hyun Boo
    • Bulletin of the Korean Chemical Society
    • /
    • 제12권4호
    • /
    • pp.429-433
    • /
    • 1991
  • The photoinduced electron transfer reactions of N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) in various polar solvents were studied by measuring time-resolved fluorescence. The temperature dependence on the fluorescence decay rate in acetonitrile, methanol, ethanol and buthanol was carried out to obtain the activation energy and Arrehnius factor for the photoinduced electron transfer reaction. It was found that as the dielectric constant of the solvent increases, the activation energy and the reaction rate increase. This implys that the Arrehnius factor is important in controlling the photoinduced electron transfer reaction rate. In water, TMPD exists in three forms (cationic, protonated and neutral forms) due to the high dielectric constant and strong proton donating power of water. The photoinduced electron transfer reaction was found to be very fast (< 50 ps) and also the long liverd component in the fluorescence decay profile attributable to the photoexcited protonated form of TMPD was observed. Probably, the reaction pathway and the reaction coordinate seem to be different depending on the solvents studied here.